Stars

Size comparison between the Sun and TRAPPIST-1 (Image ESO)

An article published in the journal “The Astrophysical Journal” describes the most accurate measurement of the characteristics of the ultra-cold dwarf star TRAPPIST-1. A team led by astronomer Valérie Van Grootel of the University of Liège in Belgium used new observations and analysis techniques to refine the measurements of TRAPPIST-1. It’s become the subject of a lot of research after the confirmation in February 2017 that 7 rocky planets orbit this tiny star and knowing its characteristics with precision helps to study the whole system.

Artist's concept of a star in formation with signals from methanol (Image courtesy Wolfgang Steffen/Boy Lankhaar et al. (molecules: Wikimedia Commons/Ben Mills))

An article published in the journal “Nature Astronomy” describes a research that provides a way to use methanol to measure magnetic fields existing in space. A team of researchers led by Boy Lankhaar of the Chalmers Univerisity in Gothenburg, Sweden, studied the properties of methanol to use it in the calculation of magnetic fields that play an important role in the formation of massive stars.

ASASSN-15no (Image courtesy ASAS-SN / DSS)

An article to be published in the journal “Monthly Notices of the Royal Astronomical Society” describes the study of the supernova ASASSN-15no. A team of astronomers, especially from the National Institute of Astrophysics in Padua, Italy, led by Stefano Benetti used a number of telescopes to observe an explosion that was initially hidden by a thick layer of gas and dust ejected by the progenitor star a few years before. For this reason, the astronomers have called it a supernova that plays hide and seek but in the end it popped out and was at least ten times brighter than normal.

The Cartwheel Galaxy (Image ESA/Hubble & NASA)

An image captured by the Hubble Space Telescope shows the Cartwheel Galaxy shows its particular structure that combines features of a lenticular galaxy and a ring galaxy. Its unusual shape is probably the result of a collision with another smaller galaxy that caused a series of shock waves in its nucleus that pushed gas and dust outwards. A long-term consequence of that accumulation of gas in the outer ring is the birth of a lot of massive stars, visible in blue.

The possible look of TRAPPIST-1's planets (Image NASA/R. Hurt/T. Pyle)

An article published in the journal “Astronomy & Astrophysics” describes a study of the internal structure and tidal warming of the 7 planets of the ultra-cool dwarf star TRAPPIST-1 system. Amy C. Barr, Vera Dobos, and László L. Kiss created models of those 7 planets, concluding that two of them are most likely to be habitable because the temperatures on their surface could allow the presence of liquid water.